As the Occupy Wall Streeters are beginning to discover, and homeless people have known all along, many ordinary and biologically necessary activities are illegal when performed in American streets — not just urinating but sitting, lying down and sleeping. In Sarasota, Fla., for example, it is illegal for someone to sleep in public if, when awakened, he says he has “no other place to live.”

Such prohibitions on homelessness began to take shape in the 1980s, along with the ferocious growth of the financial industry — Wall Street and all its tributaries throughout the nation. That was also the era in which we stopped being a nation that manufactured much beyond weightless, invisible “financial products,” leaving the old industrial working class to carve out a livelihood at places like Wal-Mart.

As it turned out, the captains of the new “casino economy” — the stockbrokers and investment bankers — were highly sensitive, one might say finicky, individuals, easily offended by having to step over the homeless in the streets or pass by them in commuter train stations. In an economy where a centimillionaire could turn into a billionaire overnight, the poor and unwashed were a major buzz kill. Starting with Mayor Rudy Giuliani’s New York, city after city passed “broken windows” or “quality of life” ordinances that made it dangerous for the homeless to loiter or, in some cases, even look “indigent” in public spaces.